The constitution of the United Kingdom is the sum of laws and principles that make up the body politic of the United Kingdom. It concerns both the relationship between the individual and the state, and the functioning of the legislature, the executive and judiciary. Unlike many other nations, the UK has no single constitutional document. This is sometimes expressed by stating that it has an uncodified or "unwritten" constitution.[1] Much of the British constitution is embodied in written documents, within statutes, court judgments, works of authority and treaties. The constitution has other unwritten sources, including parliamentaryconstitutional conventions.[2]

Since the Glorious Revolution in 1688, the bedrock of the British constitution has traditionally been the doctrine of parliamentary sovereignty, according to which the statutes passed by Parliament are the UK's supreme and final source of law.[3] It follows that Parliament can change the constitution simply by passing new Acts of Parliament. There is some debate about whether this principle remains valid,[4] particularly in light of the UK's membership in the European Union.[5]

One of several shelves full of books about the UK constitution at a law library

Acts of Parliament are bills which have received the approval of Parliament – that is, the Monarch, the House of Lords and the House of Commons. On rare occasions, the House of Commons uses the "Parliament Acts" (the Parliament Act 1911 and the Parliament Act 1949) to pass legislation without the approval of the House of Lords. It is unheard of in modern times for the Monarch to refuse to assent to a bill, though the possibility was contemplated by George V in relation to the fiercely controversial Government of Ireland Act 1914.[7] Acts of Parliament are among the most important sources of the constitution. According to the traditional view, Parliament has the ability to legislate however it wishes on any subject it wishes. For example, most of the iconic mediaeval statute known as Magna Carta has been repealed since 1828, despite previously being regarded as sacrosanct. It has traditionally been the case that the courts are barred from questioning any Act of Parliament, a principle that can be traced back to the mediaeval period.[8] On the other hand, this principle has not been without its dissidents and critics over the centuries, and attitudes among the judiciary in this area may be changing.[9][better source needed] One consequence of the principle of parliamentary sovereignty is that there is no hierarchy among Acts of Parliament: all parliamentary legislation is, in principle, of equal validity and effectiveness. However, the judgment of Lord Justice Laws in the Thoburn case in 2002 indicated that there may be a special class of "constitutional statutes" such as Magna Carta, the Human Rights Act 1998, the European Communities Act 1972, the Act of Union and Bill of Rights which have a higher status than other legislation. This part of his judgment was "obiter" (i.e. not binding) – and, indeed, was controversial. It remains to be seen whether the doctrine will be accepted by other judges.

Treaties do not, on ratification, automatically become incorporated into UK law. Important treaties have been incorporated into domestic law by means of Acts of Parliament. The European Convention on Human Rights, for example, was given "further effect" into domestic law through the preamble of the Human Rights Act 1998. Also, the Treaty of Union of 1707 was important in creating the unitary state which exists today. The treaty was between the governments of England and Scotland and was put into effect by two Acts of Union which were passed by the Parliaments of England and Scotland, respectively. The Treaty, along with the subsequent Acts, brought into existence the Kingdom of Great Britain, uniting the Kingdom of England and the Kingdom of Scotland.

Common law legal systems exist in Northern Ireland and in England and Wales but not in Scotland which has a hybrid system (see Scots law) which involves a great deal of Common Law. Court judgments also commonly form a source of the constitution: generally speaking in English Law, judgments of the higher courts form precedents or case law that binds lower courts and judges; Scots Law does not accord the same status to precedent and judgments in one legal system do not have a direct effect in the other legal systems.[10] Historically important court judgments include those in the Case of Proclamations, the Ship money case and Entick v Carrington, all of which imposed limits on the power of the executive. A constitutional precedent applicable to British colonies is Campbell v. Hall, which effectively extended those same constitutional limitations to any territory which has been granted a representative assembly.

Many British constitutional conventions are ancient in origin, though others (like the Salisbury Convention) date from within living memory. Such conventions, which include the duty of the Monarch to act on the advice of his or her ministers, are not formally enforceable in a court of law; rather, they are primarily observed "because of the political difficulties which arise if they are not."[11]

Works of authority is the formal name for works that are sometimes cited as interpretations of aspects of the UK constitution. Most are works written by nineteenth- or early-twentieth-century constitutionalists, in particular A. V. Dicey, Walter Bagehot and Erskine May.

In the 19th century, A. V. Dicey, a highly influential constitutional scholar and lawyer, wrote of the twin pillars of the British constitution in his classic work Introduction to the Study of the Law of the Constitution (1885). These pillars are the principle of Parliamentary sovereignty and the rule of law. Parliamentary sovereignty means that Parliament is the supreme law-making body: its Acts are the highest source of English law (the concept of parliamentary sovereignty is disputed in Scots law, see MacCormick v Lord Advocate).

According to the doctrine of parliamentary sovereignty, Parliament may pass any legislation that it wishes. Historically, "No Act of Parliament can be unconstitutional, for the law of the land knows not the word or the idea."[13] By contrast, in countries with a codified constitution, the legislature is normally forbidden from passing laws that contradict that constitution: constitutional amendments require a special procedure that is more arduous than that for regular laws.[14]

There are many Acts of Parliament which themselves have constitutional significance. For example, Parliament has the power to determine the length of its term. By the Parliament Acts 1911 and 1949, the maximum length of a term of parliament is five years but this may be extended with the consent of both Houses. This power was most recently used during World War II to extend the lifetime of the 1935 parliament in annual increments up to 1945. Parliament also has the power to change the make-up of its constituent houses and the relation between them. Examples include the House of Lords Act 1999 which changed the membership of the House of Lords, the Parliament Acts 1911 and 1949 which altered the relationship between the House of Commons and the House of Lords and the Reform Act 1832 which made changes to the system used to elect members of the House of Commons.

The House of Commons alone possesses the power to pass a motion of no confidence in the Government, which requires the Government either to resign or seek fresh elections (this principle was codified in the Fixed-term Parliaments Act 2011—see below for more details). Such a motion does not require passage by the Lords or Royal Assent.

Parliament traditionally also has the power to remove individual members of the government by impeachment (with the Commons initiating the impeachment and the Lords trying the case), although this power has not been used since 1806. By the Constitutional Reform Act 2005 it has the power to remove individual judges from office for misconduct.

Additionally, Dicey has observed that the constitution of Belgium (as it stood at the time) "comes very near to a written reproduction of the English constitution."[17]

There are nine regions of England for central government administration but (London aside) they have no separate legislatures.

Parliament contains no chamber comparable to the United States Senate (which has equal representation from each state of the USA) or the German Bundesrat (whose membership is selected by the governments of the States of Germany). England contains over 80% of the UK's population, produces over 80% of its combined gross domestic product and contains the capital city.

In England the established church is the Church of England. In Scotland, there is no state church, the Church of Scotland having been disestablished by the Church of Scotland Act 1921; Wales and Northern Ireland have no established church. England and Wales share the same legal system, while Scotland and Northern Ireland each has its own distinct legal system. These distinctions were created as a result of the United Kingdom being created by the union of separate countries according to the terms of the 1706 Treaty of Union, ratified by the 1707 Acts of Union.

Reforms since 1997 have decentralised the UK by setting up a devolved Scottish Parliament and assemblies in Wales and Northern Ireland. The UK was formed as a unitary state, though Scotland and England retained separate legal systems. Some commentators[21] have stated the UK is now a "quasi-federal" state: it is only "quasi" federal, because (unlike the other components of the UK) England has no legislature of its own, and is directly ruled from Westminster (the devolved bodies are not sovereign and could, in theory at least, be repealed by Parliament – unlike "true" federations such as the United States where the constituent states share sovereignty with the federal government). Attempts to extend devolution to the various regions of England have stalled, and the fact that Parliament functions both as a British and as an English legislature has created some dissatisfaction (the so-called "West Lothian question").

Under European Law, as developed by the ECJ, the EC Treaty created a "new legal order" under which the validity of European Union law cannot be impeded by national law; though the UK, like a number of other EU members, does not share the ECJ's monist interpretation unconditionally, it accepts the supremacy of EU law in practice.[22]:344 Because, in the UK, international law is treated as a separate body of law, EU law is enforceable only on the basis of an Act of Parliament, such as the European Communities Act 1972, which provides for the supremacy of EU law.[23][22]:344 The supremacy of EU law was confirmed by the House of Lords in the Factortame litigation, in which part of the Merchant Shipping Act 1988 was "disapplied" because it conflicted with EU law. In his judgment in Factortame, Lord Bridge wrote:

[T]he supremacy within the European Community of Community law over the national law of member states ... was certainly well established in the jurisprudence of the European Court of Justice long before the United Kingdom joined the Community. Thus, whatever limitation of its sovereignty Parliament accepted when it enacted the European Communities Act 1972 was entirely voluntary. Under the terms of the Act of 1972 it has always been clear that it was the duty of a United Kingdom court, when delivering final judgment, to override any rule of national law found to be in conflict with any directly enforceable rule of Community law. ... Thus there is nothing in any way novel in according supremacy to rules of Community law in those areas to which they apply and to insist that, in the protection of rights under Community law, national courts must not be inhibited by rules of national law from granting interim relief in appropriate cases is no more than a logical recognition of that supremacy.[22]:367–368[24]

On one analysis, EU law is simply a subcategory of international law that depends for its effect on a series of international treaties (notably the Treaty of Rome and the Maastricht Treaty). It therefore has effect in the UK only to the extent that Parliament permits it to have effect, by means of statutes such as the European Communities Act 1972, and Parliament could, as a matter of British law, unilaterally bar the application of EU law in the UK simply by legislating to that effect.[22][26] However, at least in the views of some British authorities, the doctrine of implied repeal, which applies to normal statutes, does not apply to "constitutional statutes", meaning that any statute that was to have precedence over EU law (thus disapplying the 1972 European Communities Act) would have to provide for this expressly or in such a way as to make the inference "irresistible".[22]:369 The actual legal effect of a statute enacted with the express intention of taking precedence over EU law is as yet unclear.[27] However, it has been stated that if Parliament were to expressly repudiate its treaty obligations the courts would be obliged to give effect to a corresponding statute:

“

If the time should come when our Parliament deliberately passes an Act – with the intention of repudiating the Treaty or any provision of it – or intentionally of acting inconsistently with it – and says so in express terms – then . . . it would be the duty of our courts to follow the statute of our Parliament" (per Lord Denning in Macartys Ltd v Smith [1979] ICR at p. 789)"[28]

”

In 2011 parliament passed the European Union Act which states in clause 18 (Status of EU law dependent on continuing statutory basis): "Directly applicable or directly effective EU law (that is, the rights, powers, liabilities, obligations, restrictions, remedies and procedures referred to in section 2(1) of the European Communities Act 1972) falls to be recognised and available in law in the United Kingdom only by virtue of that Act or where it is required to be recognised and available in law by virtue of any other Act."[29]

Following the accession of the UK to European Economic Community (now the European Union) in 1972, the UK became bound by European law and more importantly, the principle of the supremacy of European Union law. According to this principle, which was outlined by the European Court of Justice in 1964 in the case of Costa v. ENEL, laws of member states that conflict with EU laws must be disapplied by member states' courts. The conflict between the principles of the primacy of EU law and of parliamentary supremacy was illustrated in the judgment in Thoburn v Sunderland City Council,[30] which held that the European Communities Act 1972, the Act that initiated British involvement in the EU, could not be implicitly repealed simply by the passing of subsequent legislation inconsistent with European law. The court went further and suggested that the 1972 Act formed part of a category of special "constitutional statutes" that were not subject to implied repeal. This exception to the doctrine of implied repeal was something of a novelty, though the court stated that it remained open for Parliament to expressly repeal the Act.[31] It is politically inconceivable at the present time that Parliament would do so and constitutional lawyers have also questioned whether such a step would be as straightforward in its legal effects as it might seem. The Thoburn judgment was handed down only by the Divisional Court (part of the High Court), which occupies a relatively low level in the legal system.

The monarch will ask the leader of the majority party in the House of Commons to form a government, and if there is no majority party, the person who appears most likely to command the confidence of the House of Commons to serve as Prime Minister and form a government.[33]

The monarch will ask a member of the House of Commons (rather than the House of Lords or someone outside Parliament) to form a government. It remains possible, however, for a caretaker Prime Minister to be drawn from the House of Lords.

All ministers are to be drawn from the House of Commons or the House of Lords.

The House of Lords will accept any legislation that was in the Government's manifesto (the Salisbury Convention) – in recent years this convention has been broken by the Lords, though the composition of the Lords (which was the justification for the convention) has radically changed since the convention was introduced.

Under the British constitution, sweeping executive powers, known as the royal prerogative, are nominally vested in the monarch. In exercising these powers the monarch normally defers to the advice of the prime minister or other ministers. This principle, which can be traced back to the Restoration, was most famously articulated by the Victorian writer Walter Bagehot as "the Queen reigns, but she does not rule". The precise extent of the royal prerogative has never formally been delineated, but in 2004, Her Majesty's Government published some of the powers, in order to be more transparent:[34]

The power to appoint bishops and archbishops of the Church of England.

Foreign powers

The power to ratify and make treaties

The power to declare War and Peace

The power to deploy the Armed Forces overseas

The power to recognise states

The power to credit and receive diplomats

The most important prerogative still personally exercised by the monarch is the choice of whom to appoint Prime Minister. The most recent occasion when the monarch has had to exercise these powers was in February 1974, when Edward Heath resigned from the position of prime minister after failing to win an overall majority at the General Election or to negotiate a coalition. Queen Elizabeth II appointed Harold Wilson, leader of the Labour Party, as prime minister, exercising her prerogative after extensive consultation with the Privy Council. The Labour Party had the largest number of seats in the House of Commons, but not an overall majority. The 2010 general election also resulted in a hung parliament. After several days of negotiations, between the parties, Queen Elizabeth II invited David Cameron to form a government on the advice of the outgoing prime minister Gordon Brown.

The monarch formerly enjoyed the power to dissolve Parliament (normally on the request of the prime minister). However, this power was explicitly removed from the monarch by the Fixed-term Parliaments Act 2011. The last monarch to dismiss a prime minister who had not suffered a defeat on a motion of confidence in the House of Commons, or to appoint a prime minister who clearly did not enjoy a majority in that House, was William IV who in 1834 dismissed the Government of Lord Melbourne, replacing him with Robert Peel (The Duke of Wellington briefly heading a caretaker ministry as Peel was on holiday in Italy at the time). Peel resigned after failing to win the 1835 General Election — prior to the 1832 Reform Act, which reduced the number of rotten and pocket boroughs, it would have been very unusual for a government with Royal backing to be defeated in this way.

Queen Victoria was the last monarch to veto a ministerial appointment. In 1892, she refused William Ewart Gladstone's advice to include Henry Labouchère (a radical who had insulted the Royal Family) in the Cabinet.[36] The last monarch to veto legislation passed by Parliament was Queen Anne, who withheld assent from the Scottish Militia Bill 1708. However, the possibility that a royal veto might be exercised independently by the monarch remained for at least two further centuries. Pitt the Younger resigned in 1801 when George III made clear that he would veto Catholic Emancipation, which he regarded as a breach of his oath to uphold the Church of England—the measure did not pass until 1829 when George IV was persuaded to drop his opposition. As late as 1914, George V took legal advice on withholding the Royal Assent from the Third Irish Home Rule Bill, which the Liberal government was pushing through parliament having recently removed the Lords' veto (Parliament Act 1911) and in the teeth of threatened armed resistance in Ulster. The King decided that he should not withhold the Assent without "convincing evidence that it would avert a national disaster, or at least have a tranquillizing effect on the distracting conditions of the time".[37]

The Royal Prerogative is not unlimited; this was established in the Case of Proclamations (1610), which confirmed that no new prerogative can be created and that Parliament can abolish individual prerogatives. However, as part of Parliamentary Sovereignty, Parliament could create new prerogatives if it so wished regardless. Parliament possesses the power to remove powers from the Royal Prerogative: this was done in the Fixed-term Parliaments Act 2011 which removed the Royal Prerogative to dissolve Parliament. However, the monarch's consent is required before Parliament may pass legislation removing such powers: this was seen when the second reading of the Military Action Against Iraq (Parliamentary Approval) Bill, which would have removed the monarch's ability to authorize military action without Parliamentary approval, had to be abandoned because the monarch (on the advice of her government) refused to grant such consent.[38]

The monarch's approval ("Queen's consent") is required before Parliament may debate or pass proposed legislation affecting the Royal Prerogative, or the hereditary revenues, personal property, or personal interests of the Crown, the Duchy of Lancaster, or the Duchy of Cornwall.[39] The consent of the Duke of Cornwall (who is also the Prince of Wales) is also required before Parliament may debate or pass proposed legislation affecting the Duchy of Cornwall.[39]

It is the monarch's constitutional duty to appoint a Prime Minister who can command support of a majority in the House of Commons. When one party has an absolute majority in the House of Commons, the monarch appoints the leader of that party as prime minister. When there is a hung parliament, or the identity of the leader of the majority party is not clear (as was often the case for the Conservative Party up to the 1960s, and for all parties in the nineteenth century), the monarch has more flexibility in his or her choice. The monarch appoints and dismisses other ministers on the advice of the prime minister (and such appointments and dismissals occur quite frequently as part of cabinet reshuffles). The prime minister, together with other ministers, form the Government. The Government often includes ministers whose posts are sinecures (such as the Chancellor of the Duchy of Lancaster) or ministers with no specific responsibilities (minister without portfolio): such positions may be used by the prime minister as a form of patronage, or to reward officials such as the Chairman of the ruling Party with a governmental salary.

If the Commons votes against the Government on a motion of no confidence, the Fixed-term Parliaments Act 2011 specifies that Parliament automatically dissolves unless a subsequent motion of confidence is passed within fourteen days. The Prime Minister and government would have the option of resigning in order to allow a replacement government the chance to obtain a vote of confidence within the required timeframe, or remaining in office to fight the subsequent general election.

The prime minister and all other ministers take office immediately upon appointment by the monarch. In the United Kingdom, unlike many other countries, there is no requirement for a formal vote of approval by the legislature (either of the Government as a whole or of its individual members) before they may assume office.

The prime minister and all other Ministers normally serve concurrently as members of the House of Commons or House of Lords, and are obliged by collective responsibility to cast their Parliamentary votes for the Government's position, regardless of their personal feelings or the interests of their constituents. The prime minister is normally a member of the House of Commons. The last prime minister to be a member of the House of Lords was Alec Douglas-Home; however, he resigned from the Lords and became a member of the Commons shortly after his appointment as prime minister in 1963 (there was a period of about two weeks during which he served as prime minister despite belonging to neither House). The last prime minister to serve a full administration from the House of Lords was Robert Cecil, 3rd Marquess of Salisbury, who served until 1902.

Thus the executive ("Her Majesty's Government") is "fused" with Parliament. Because of a number of factors, including the decline of the monarch and the House of Lords as independent political actors, an electoral system that tends to produce absolute majorities for one party in the Commons, and the strength of party discipline in the Commons (including the built-in payroll vote in favour of the Government), the prime minister tends to have sweeping powers checked only by the need to retain the support of his or her own MPs. The phrase elective dictatorship was coined by former Lord ChancellorQuintin Hogg in 1976 to highlight the enormous potential power of government afforded by the constitution.[41]

The need of a prime minister to retain the support of her own MPs was illustrated by the case of Margaret Thatcher, who resigned in 1990 after being challenged for the leadership of the Conservative Party. The strength of party discipline within the Commons, enforced by the whip system, is shown by the fact that the two most recent motions of no confidence in which a Government was defeated occurred in 1924 and 1979.

Vacancies in the Supreme Court are filled by the monarch based on the recommendation of a special selection commission consisting of that Court's President, Deputy President, and members of the judicial appointment commissions for the three judicial systems of the UK. The choice of the commission may be vetoed by the Lord Chancellor (a government minister). Members of the Supreme Court may be removed from office by Parliament, but only for misconduct.

Judges may not sit or vote in either House of Parliament (before the 2005 Act, they had been permitted to sit and vote in the House of Lords).

Parliament retains authority to pass laws regulating the Church of England. In practice, much of this authority is delegated to the Church's General Synod. The appointment of bishops and archbishops of the Church falls within the royal prerogative. In current practice, the Prime Minister makes the choice from two candidates submitted by a commission of prominent Church members, then passes his choice on to the monarch. The Prime Minister plays this role even though he himself is not required to be a member of the Church of England or even a Christian—for example Clement Attlee was an agnostic who described himself as "incapable of religious feeling".[44]

Unlike many nations in continental Europe, the United Kingdom does not directly fund the established church with public money (although many publicly funded voluntary aided schools are run by religious foundations, including those of the Church of England). Instead, the Church of England relies on donations, land and investments.

Administrative law is often called "public law". Administrative law restricts the exercise of the government's power over public administration; it covers areas such as policing, prisons, urban planning, education, the environment and immigration. It ensures the exercise of the government's power takes place within a legislative framework. This means the legal responsibilities of governmental bodies are properly defined and, at the same time, the rights and interests of the country's citizens are protected from the misuse or abuse of government power over public administration.[45]

The legal scholar Eric Barendt argues that the uncodified nature of the United Kingdom constitution does not mean it should not be characterised as a "constitution", but also claims that the lack of an effective separation of powers, and the fact that parliamentary sovereignty allows Parliament to overrule fundamental rights, makes it to some extent a 'facade' constitution.[46]

In one article, Lord Scarman presents a spirited argument for a written constitution for the UK, but still refers to the 1688 compromise and resulting Acts of Parliament as a constitution.[47]

A. V. Dicey identified that ultimately "the electorate are politically sovereign," and Parliament is legally sovereign.[48] Barendt argues that the greater political party discipline in the House of Commons that has evolved since Dicey's era, and the reduction in checks on governmental power, has led to an excessively powerful government that is not legally constrained by the observance of fundamental rights.[46] A Constitution would impose limits on what Parliament could do. To date, the Parliament of the UK has no limit on its power other than the possibility of extra-parliamentary action (by the people) and of other sovereign states (pursuant to treaties made by Parliament and otherwise).

Proponents of a codified constitution argue it would strengthen the legal protection of democracy and freedom.[49] As a strong advocate of the "unwritten constitution", Dicey highlighted that English rights were embedded in the general English common law of personal liberty, and "the institutions and manners of the nation".[50] Opponents of a codified constitution argue that the country is not based on a founding document that tells its citizens who they are and what they can do. There is also a belief that any unwarranted encroachment on the spirit of constitutional authority would be stiffly resisted by the British people, a perception expounded by the 19th century American judge Justice Bradley in the course of delivering his opinion in a case heard in Louisiana in 1873: "England has no written constitution, it is true; but it has an unwritten one, resting in the acknowledged, and frequently declared, privileges of Parliament and the people, to violate which in any material respect would produce a revolution in an hour."[51]

Gordon Brown launched a "Governance of Britain" process when he took over as PM in 2007. This was an ongoing process of constitutional reform with the Ministry of Justice as lead ministry. The Constitutional Reform and Governance Act 2010 is a piece of constitutional legislation. It enshrines in statute the impartiality and integrity of the UK Civil Service and the principle of open and fair recruitment. It enshrines in law the Ponsonby Rule which requires that treaties are laid before Parliament before they can be ratified.

The Coalition Government, formed in May 2010, proposed a series of further Constitutional reforms in their coalition agreement. Consequently, the Parliamentary Voting System and Constituencies Act 2011 and the Fixed-term Parliaments Act 2011 were passed. The Acts will reduce the number of MPs in the House of Commons from 650 to 600, change the way the UK is divided into parliamentary constituencies, introduce a referendum on changing the system used to elect MPs and take the power to dissolve Parliament away from the monarch. The Coalition has also promised to introduce legislation on the reform of the House of Lords. A referendum on the voting system was rejected by 67%, and therefore all reforms regarding the voting system were dropped.[52] Conservatives forced the government to drop House Of Lord reforms, to which the Liberal Democrats said they would refuse to support changes to the boundaries of constituencies. (The Liberal Democrats believing such changes favoured the Conservatives).

^H Barnett, Constitutional and Administrative Law (5th edn Cavendish 2005) 9, "A written constitution is one contained within a single document or a [finite] series of documents, with or without amendments"

^Tomkins, Adam (2003). Public Law. Oxford University Press. p. 120. ISBN978-0-19-926077-5. As far as English public law is concerned, even after Factortame Parliament may relatively easily legislate in violation of Community law and moreover may do so in such a way that the domestic courts have no option but to uphold and enforce the legislation.

^Craig, Paul; Grainne De Burca; P. P. Craig (2007). EU Law: Text, Cases and Materials (4th ed.). Oxford: Oxford University Press. p. 371. ISBN978-0-19-927389-8. It is however unclear as yet what the UK courts would do if Parliament sought expressly to derogate from a provision of EU law, while still remaining in the EU.